Apparatuses comprising various means for unwinding, forwarding, debossing or embossing, and/or perforating, and rewinding of a ribbon or web of thermoplastic film are disclosed in the prior art: see for instance, U.S. Pat. No. Re. 23,910, Method of And Apparatus For Producing Textured Films which issued Dec. 14, 1954 to L. H. Smith et al.; U.S. Pat. No. 3,054,148, Process Of Producing A Perforated Thermoplastic Sheet which issued Sep. 18, 1962 to W. F. Zimmerli; and U.S. Pat. No. 2,567,275, Apparatus And Method Of Goffering Thermoplastic-tic Materials which issued Sep. 11, 1951 to R. Colombo. See also U.S. Pat. No. 3,674,221, Dynamic Stress-Strain Testing Of Ribbons Of Film which issued Jul. 4, 1972 to Coenraad E. Riemersma.
The prior art also discloses various methods of making perforated members: see for instance U.S. Pat. No. 3,453,712, Method Of Making A Porous Roll which issued Jul. 8, 1969 to R. G. MacKendrick; U.S. Pat. No. 3,613,208, Method Of Fabricating A Perforated Panel For A Vacuum Work-Holder Or Chuck which issued Oct. 19, 1971 to H. A. Seberg et al.; and U.S. Pat. No. 3,247,579, Circuit Fabrication Method which issued Apr. 26, 1966 to L. H. Cattermole et al.
Methods and apparatuses for imparting a three-dimensional polymeric web having improved tactile impression are disclosed in U.S. Pat. No. 4,151,240, Method for Debossing and Perforating a Running Ribbon of Thermoplastic Film, which issued Apr. 24, 1979 to Lucas et al.; and U.S. Pat. No. 4,601,868, Method of Imparting a Three-Dimensional Fibr-Like Appearance and Tactile Impression to a Running Ribbon of Thermoplastic Film, which issued Jul. 22, 1986 to Radel et al.
Other methods and apparatuses have been disclosed for making polymeric webs exhibiting a soft and silky tactile impression. For example, U.S. Pat. No. 4,609,518 and U.S. Pat. No. 4,629,643, each issued to Curro et al., and issued Sep. 2, 1986, and Dec. 16, 1986, respectively, disclose an apparatus for forming a polymeric web having large apertures and a plurality of fine-scale apertures.
The above-mentioned references are representative of various methods and apparatuses for embossing or debossing polymeric films on a supporting framework, often termed a forming structure or screen. In particular, many of these references disclose the use of cylindrical metal screens comprising an interconnecting network defining a plurality of apertures to which a polymeric film can conform when impinged upon by a fluid such as jets of water or heated air. The plurality of apertures provides for a relatively high open area through the screen through which water, for example, can pass through. One example of the use of such screens for the application of high pressure liquid jet or stream to a web of polymeric film is disclosed in U.S. Pat. No. 4,778,644, issued to Curro et al., and issued Oct. 18, 1988.
Metal forming structures, e.g., screens, of the type disclosed above suffer from a relatively short useful life. That is, because of the relatively thin interconnecting network (necessary to provide sufficient open area for film formation), prior art screens have a limited useful life when used in a commercial process involving subjecting the screen to high pressure water jets in a continuous cyclic process. Metal screens of the type disclosed in the above-mentioned Radel, for example, are very expensive to make, so that the cost of products made thereon is negatively impacted by a limited useful life. It is believed that the limited useful life is due to fatigue failure of present screens due to the cyclic stress/relaxation experienced when the screen is part of a cylindrical forming structure that rotates past high pressure liquid jets.
Accordingly, there is a need for a more durable forming screen useful for making three-dimensional formed film webs.